Sports & physical activity during and after treatment

Yes — in most cases, some level of physical activity is not only safe but encouraged during childhood cancer treatment. The key is matching the activity to where your child is in their treatment cycle. On days when blood counts are in a safe range and your child has energy, gentle movement such as short walks, light stretching, or casual outdoor play is beneficial. It can help reduce treatment-related fatigue, support mood, and maintain some muscle strength. On days after chemotherapy when counts are low, or when your child is feverish and unwell, rest is the right choice. Your child's oncology team will advise on specific blood count thresholds that should guide activity. The important message is that rest-all-the-time is not always the most helpful approach — gentle movement, even in small amounts, is part of good supportive care.

Yes, certain activities carry real risks during treatment and should be avoided. Contact sports — football, cricket with hard balls, wrestling — should be avoided when platelet counts are low, because a knock or fall carries a higher risk of bleeding that is difficult to stop. Swimming in public pools and shared changing areas should be avoided when white blood cell counts are low, because the immune system is less able to fight infections picked up from shared water or surfaces. High-impact activities such as jumping on trampolines or running on hard surfaces may need to be limited for children with bone involvement or who are at risk of fractures. Your oncology nurse or physiotherapist will be able to give you a personalised list based on your child's diagnosis, treatment stage, and current blood results — always check before starting something new.

There is no single answer — it depends on the cancer type, the treatment received, how long treatment lasted, and your child's current fitness level. For many children who had a shorter treatment course without major complications, a gradual return to sport can begin within weeks of completing treatment, starting with light activity and building up over several months. For children who received treatment affecting the heart or lungs — such as chest radiation or certain types of chemotherapy — a medical review, and sometimes a heart function test, should happen before returning to vigorous or competitive sport. For children who had surgery to a limb or who use a prosthesis, adapted sport is often possible, and a physiotherapist with experience in paediatric oncology rehabilitation can be an enormous help. Do not rush the return. A slow, steady build-up is safer and more sustainable than jumping straight back to pre-diagnosis activity levels.

Most forms of sport are suitable for childhood cancer survivors, and the best sport is usually the one your child enjoys and will stick with. Physical activity in survivorship is particularly valuable for cardiovascular health, bone strength, muscle mass, and mental wellbeing. Weight-bearing activities — walking, running, dancing, ball sports, martial arts — are especially good for bone health, which can be affected by some cancer treatments. Swimming and cycling are excellent for cardiovascular fitness and are very joint-friendly. Team sports have the added benefit of social connection and fun, which supports emotional recovery. If your child had treatment affecting the heart or lungs, low- to moderate-intensity aerobic activities are a good starting point, with the team monitoring exercise tolerance. A sports medicine doctor or physiotherapist familiar with paediatric survivorship can help create a plan that matches your child's interests with their medical history.

Fatigue is the most commonly reported side effect of childhood cancer treatment and can persist for months or even years after treatment ends in some children. If your child is saying they are too tired to move, take it seriously — but also know that the relationship between cancer fatigue and exercise is more complex than it might seem. Research consistently shows that gentle, graded physical activity actually reduces cancer-related fatigue over time, even though it feels counterintuitive. Starting very small — a five-minute walk, a gentle stretch session, a slow cycle around the garden — and increasing gradually is more effective than waiting until your child 'feels ready.' If fatigue is severe, long-lasting, or getting worse rather than better, discuss this with the oncology team. Persistent severe fatigue can sometimes signal other treatable issues such as anaemia, thyroid problems, or depression, and these should be properly investigated rather than attributed to cancer alone.

For many children, especially those who had limb surgery, bone involvement, or prolonged periods of reduced activity, seeing a physiotherapist experienced in paediatric oncology rehabilitation before returning to sport is strongly recommended. A physiotherapist can assess your child's current strength, flexibility, balance, and fitness; identify any areas of weakness or stiffness from treatment or prolonged rest; and design a personalised, progressive programme that safely builds back to sport participation. For children who have had major surgery, amputations, or limb-sparing procedures, physiotherapy is often an essential part of the return-to-activity pathway. Even for children without major surgical history, a few sessions of guided physiotherapy can give parents and children confidence that they are building back safely. Ask your oncology team to refer you — this is a standard part of comprehensive survivorship care, not a luxury.